Composite ionic conductors based on magnesium salts and sol–gel derived silicate–tetraethylene glycol hybrids have been synthesized. The structure of these materials has been studied by FT-IR, FT-Raman, 29Si and 13C NMR and XRD techniques. The composite systems can be best described as diphasic with silicate as fillers in the organic phase that provides solubility of the ionic dispersants. The ionic interactions in the matrix are clearly observed in the FT-Raman spectra. The ionic conductivity is determined to be of the order of 10−7 to 10−5 S cm−1 at room temperature for MgCl2 and Mg(ClO4)2 salts respectively. The conductivity reaches 10−4 and 10−3 S cm−1 at 80 °C respectively.